Wednesday, May 26, 2010

Constructive criticism

I've been thinking about constructive empiricism. (This is a boiled down version of a more rambling post over at my blog.)


Van Fraassen doesn't see the disagreement between realists and constructive empiricists as being about what we ought to believe. Instead, he sees the dispute as being about the proper aim of science. Here's one way he put the point:
Scientific realism and constructive empiricism are. as I understand them, not epistemologies but views of what science is. Both views characterize science as an activity with an aim - a point, a criterion of success - and construe (unqualified) acceptance of science as involving the belief that science meets that criterion. According to scientific realism the aim is truth (literally true theories about what things are like). Constructive empiricism sees the aim as not truth but empirical adequacy. [Analysis 58.3, 1998]

So scientific realism and constructive empiricism (as van Fraassen understands them) both need for there to be a purpose to science altogether - SCIENCE write large. As I intimate in my dcog paper, I don't think there is such a purpose. Even supposing that there is, however, it is not something that can be divined by a priori rumination. As van Fraassen admits, our account of what science is about must accommodate the actual history of science. It is a partly empirical enquiry responsible to evidence.

In this enquiry, the phenomena include historical documents and physical evidence. They probably also include the actual historical activities of scientists. Yet under no account is the aim or purpose of the activity itself among the phenomena. The aim of the activity is a posit, introduced as part of a philosophical-historical theory. Moreover, it is an unobservable posit.

Therefore, an agnostic (who declines to believe in the unobservable posits of even the most successful theories) must decline to believe in the aim of science. This follows regardless of what the aim of science is posited to be, so an agnostic must decline to be a constructive empiricist. This is a problem for van Fraassen, who thinks that agnosticism is a comfortable epistemic position for constructive empiricists. I see two possible replies.

First, he might stick to his agnostic guns. Refusing to believe in constructive empiricism, he still might accept it. That is, he could treat constructive empiricism as involving not a true theory about science but instead an empirically adequate one. This would involve some mental gymnastics, but being an agnostic already involves mental gymnastics. This meta move is only a small additional flourish.

Second, he might deny that the aim of science is a theoretical posit. Perhaps history is not a science. Perhaps discovering what what science is is not history. I don't see this line as terribly promising.


Van Fraassen has argued that we need a richer epistemology, one which allows for more than just binary beliefs or probabilistic degrees of belief. Moreover, he resists formal models of belief as direct representations of entities in the mind or brain. Yet he does seem to genuinely believe in states of opinion, "real epistemic attitudes, pointed to by traditional epistemology, which cannot be accommodated in the probabilist models we have developed so far" [ibid.].

As Sellars and Churchland convincingly argue, though, epistemic attitudes like this are not among the immediate phenomena of the world. We posit them as part of a (folk) psychological theory. An agnostic about scientific and folk scientific theories ought not to believe in beliefs.

Does van Fraassen acknowledge this anywhere? or is his psychological musing a personal matter rather than an announcement ex cathedra qua constructive empiricist?


  1. Interesting post! I'll try and limit myself to a few comments.

    (1) Regarding the notion that science has an aim, I think you're right that there's something fishy here. But I think van Fraassen would respond to your objection as follows. He views constructive empiricism as a view that philosophers take of what science is. (There are probably a number of passages that bear this out, but I'm thinking of "A Defence of Van Fraassen's Critique of Abductive Inference: Reply to Psillos", p. 318.) Since constructive empiricism is a philosophical view, and not a scientific one, one cannot take a constructive empiricist view of constructive empiricism. Constructive empiricism only applies to science. In this case, a scientific agnostic need not decline to believe in the aim of science, since it is not a theoretical posit of any scientific theory.

    (2) Regarding epistemic attitudes, I think van Fraassen may say something similar. I'll start by quoting his "Empiricism in Philosophy of Science".

    "Paul Churchland has argued that belief and opinion, concepts of "folk psychology," are already anachronisms. In my review of his book (van Fraassen 1981), I argued to the contrary that, as epistemology is now developing, the refinements of those concepts is a proper part of the rise of scientific philosophy (p. 247)"

    Insofar as a theory of epistemic attitudes is a philosophical theory, then van Fraassen will say something similar to what I sketched under (1), namely, that a scientific agnostic need not decline to believe in epistemic attitudes, since they are not theoretical posits of any scientific theory. I haven't read van Fraassen's review of Churchland ("Critical Study: Paul Churchland, Scientific Realism and the Plasticity of Mind", Canadian Journal of Philosophy, 11 (1981), 555-567), but it may be the place to go to answer your question.

    (3) I suspect that one big problem with van Fraassen's views in general, which may be the real target of your objections, is his commitment to a hard and fast distinction between philosophy and science. You address this briefly in (***) (on your blog), and I admit that I'm also inclined toward the view of science as "responsible enquiry". But I think van Fraassen's view of science is narrower.

    I apologize for the long-winded response. Constructive empiricism was what pulled me towards philosophy of science in the first place, and I may have gotten carried away. Also, I tried to post this on your other blog, but wasn't quite sure that I was successful, so apologies for the same comment on two different blogs.

  2. I like Van Fraasen's positions as Jonathon describes them in (1) and (3). Philosophy is not best understood, either in aim or scope, as a science. It's a bit like poetry in this regard. Indeed, holding philosophy accountable to scientific standards, would be something like demanding of poetry that it be politically correct. That happens, of course, but it has nothing to do with poetry. Philosophy can speak of science, and poetry can speak of politics, but their aim is not "scientific" or "political".

  3. I'm very much inclined to agree with you that science does not have a monolithic aim, and I'm also inclined to agree with you that science is just responsible inquiry, or something along those lines. But notice that these two views very much go together. If you think that science has a monolithic aim, then you cant ALSO think that science is just responsible inquiry.

    In other words, once you have accepted the idea that a particular aim is in part constituative of science, then it virtually follows that there will be forms of responsible inquiry that are not science. And so its not altogether implausible, once you've gone down that road, to suppose that the activity of identifying the aim of science (which as you point out is an unobservable) is not science, and might be constituted by different aims.

    Moreover, it just doesn't even strike me as a plausible view that the aim of philosophy is empirical adequacy. So though I am sympathetic with your view of philosophy as continuous with science, using it as a premise strikes me as virtually begging the question against constructive empiricism.

  4. Jonathon and Eric: Thanks for your replies.

    It's a fair cop. Van Fraassen is engaged in philosophy as something distinct from science. My criticism here is just a roundabout way of refusing to engage in that project with him. So I should grant arguendo that characterizing science isn't itself a scientific endeavour.

    Even granting that, however, it seems implausible to me that the analysis of 'belief' and other epistemic attitudes can be kept separate from empirical psychology.

  5. Oh, and Thomas: Thanks for your reply, too.

    I don't find the philosophy/poetry analogy very helpful. Poetry is usual just responsible to aesthetic and artistic standards. Philosophy, when its concerns overlap with the concerns of science, is responsible to scientific standards. If someone wrote a poem that was meant to be educational - a rhyme to teach people about the brain, for example - then the poem would be responsible for getting the brain science right. The crucial difference is that philosophical concerns overlap with obviously scientific concerns more often than poetry is meant to be educational.

  6. Any time, but you misunderstood the analogy. It's not "philosophy is to science as poetry is to science"; it's "philosophy is to science as poetry is to politics".

    In both cases, arguments are sometimes made for the overlap you mention, and sometimes for an outright reduction (to science and politics respectively). And then there are "modernist" periods of lucidity, when poets (and sometimes critics) insist on poetry as poetry "and not another thing" (as Eliot put it), and philosophers define philosophy on its own terms.

    It's a poor poet who writes a poem that will be judged on "getting the brain science right". More common, and less poor, but still not great, is the poet who tries to get the social policy right": a poem denouncing racism, for example, as opposed to a poem about what it's like to live under racism, which are two very different things.

    So I think the analogy does actually have a use in your thinking. Your view of philosophy as "scientific" is like a pretty pervasive (by mistaken) view of poetry as "political". But among poets the poverty of reducing a poem to its politics is better understood than the poverty of reducing a philosophical argument to scientific concerns is understood among philosophers.

    Philosophy is willy-nilly constrained by the concerns of science, but it should remain resolutely "irresponsible" to it.

  7. I'm not 100% certain van Fraassen would be happy with (how I interpret) Jonathan Hricko's (1), namely, the claim that scientific projects and standards can or should be severed from philosophical projects and standards. (I could certainly be wrong; I don't have the van Fraassen corpus at my mental fingertips).

    But I think van F believes empiricism is characterized by a kind of deference to science: "As in science, so in philosophy" (from the Empirical Stance).

    Elsewhere in that book, he is a bit more nuanced:
    "But [empiricism's] admiring attitude [towards science] is not directed so much to the content of the sciences as to their forms and practices of inquiry. Science is a paradigm of rational inquiry. ... But one may take it so while showing little deference to the content of any science per se.(p.63)"

    In other words: for van F, an empiricist should use the 'forms and practices of science' even in her philosophical projects.

  8. I think Greg Frost-Arnold's comments are on point as far as van Fraassen's empiricism goes. And this would show some continuity between philosophical and scientific projects for van Fraassen.

    But constructive empiricism alone doesn't get you this kind of continuity, since it only applies to science. And van Fraassen has emphasized that constructive empiricists need not be empiricists. (Here I'm thinking of section 6 of Monton and van Fraassen's "Constructive Empiricism and Modal Nominalism".) My main point in (1) was just that constructive empiricism is a philosophical position that applies only to science, and not to philosophy. I think this is consistent with Greg Frost-Arnold's comments about van Fraassen's empiricism more generally, though I may well be missing something.

    It's possible that I misread P.D. Magnus as objecting to constructive empiricism in particular, when I should have read him as objecting to van Fraassen's empiricism in general. If the latter is the target, this may pose a serious problem. My attempted response in (2) may then fall flat. It may be that constructive empiricists need not be empiricists, but it would be pretty bad if empiricists couldn't be constructive empiricists.

    Also, I recently took another look at van Fraassen's "Gideon Rosen on Constructive Empiricism" and ran across the following, from a passage where van Fraassen disputes some aspect of Rosen's take on constructive empiricism.

    "This would be a serious mistake, in my view. It would mean that the described intentional aspects of science are unobservable. Constructive empiricism would be saddled with a type of behaviourism which I am not able to take at all seriously" (p. 183).

    The suggestion is that van Fraassen might think that the aim of science is observable. I may be reading too much into this passage, and even if not, I'm not sure how to understand this suggestion. But it may be some food for thought.

  9. REPLY:
    It seems as this post has devoted a considerable amount of time developing the second of PD’s two options, i.e. that BvF doesn’t consider philosophy a science, and hence doesn’t view aims as theoretical posits. But I’d like to explore the first option a bit more, i.e. that philosophical and scientific method are largely continuous and that aims are consonant with a constructive empiricism reflecting upon itself.

    For me, the most succinct statement of the relevant BvF view comes in The Scientific Image (hereon SI—thankfully there’s no swimsuit edition):
    Science aims to give us theories which are empirically adequate; and acceptance of a theory involves a belief only that it is empirically adequate. (SI, p. 12)

    As BvF continues in the following pages of SI, accepting a theory T entails the belief that T is empirically adequate plus a pragmatic commitment, the latter of which largely involves a willingness use T to explain and pursue new research programs.

    Now, let’s turn this towards PD’s objection. One consequence of the aforementioned quotation is that
    (A) Science has an aim.
    As PD suggests, (A) sits uneasily with constructive empiricism’s agnosticism about unobservables. But given the relevant portions of SI, if (A) is a theoretical posit, BvF would have the following attitudes:
    (B) He would believe that (A) is empirically adequate, i.e. that everything it says about observables is true; and
    (C) He would be committed to (A), i.e. he would use (A) to explain various scientific practices.
    A few comments are in order. I think PD rightly characterizes the relevant observables in (B) to be facts about the history of science. More arguably, we might also include judgments of putative success (e.g. the fact that most biologists consider evolutionary theory to be superior to creationism).

    I also think that (C) counterbalances the constructive empiricist’s agnosticism about (A), and I think that this fits quite comfortably with BvF’s philosophy. Assuming commitments can be distinguished from beliefs, commitment to (A) would seem to reap all of the same fruit as belief in (A) (e.g. there would be no loss in the explanations of scientific practices).

    Furthermore, given their pragmatic nature, commitments appear to be context-sensitive, and we can thus imagine philosophical contexts that differ from other kinds of contexts (e.g. theoretical physics, other disciplines in science studies, etc.). For instance, it’s quite clear that BvF’s commitments have yielded fruitful philosophical discussion, but I could also see people in other fields thinking that the ‘mental gymnastics’ involved in these commitments are not very productive. (Think of the disparaging remarks about the futility of philosophical discussion—often raised by undergraduates or family members—that we’ve all encountered at one point or other in our careers). All of these look like pragmatic kinds of considerations. In this way, there can be differences between philosophical and scientific method, but those differences are largely consonant with the tenets of constructive empiricism.

    (To put this last point another way, I don’t think there’s as much of a difference between PD’s two options as others in this post seem to presuppose).

    Now, PD also seems to suggest that constructive empiricism’s agnosticism raises similar kinds of worries about the status of the beliefs in (B) and commitments in (C), i.e. that the following face the same problem as (A):
    (B*) People have beliefs.
    (C*) People have commitments.
    But I feel (marginally) confident that the above treatment of (A) applies to (B*) and (C*).

    Sorry for such a long post, but this is very interesting stuff!


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